In XML DTDs, one can override the declaration of an attribute declared
in an external declaration set by declaring the overriding version
earlier, e.g.:
<!DOCTYPE foo SYSTEM "mybase.dtd" [
<!ATTLIST foo bar CDATA #IMPLIED
]>
<foo bar="baz/>
Where mybase.dtd declares the element type "foo" with the attribute bar
with a different type.
I don't see an obvious way to do with with XSD using redefine. At least,
when I add a declaration to a redefine that otherwise works (to add a
new attribute not declared in the base type being redefined), Xerces 2.9
says I have a duplicate attribute declaration.
I didn't see anything about this specifically in the XSD Primer and I'm
afraid I find the formal definition largely impenetrable (at least at
this late hour).
Have I missed something?
Note, in my specific case I don't have control over the base schemas, so
I can't do something like pull the attributes to be redefined out into
their own attribute group, although I'm not sure that would solve the
problem.
Thanks,
Eliot
--
W. Eliot Kimber
Professional Services
Innodata Isogen
8500 N. Mopac, Suite 402
Austin, TX 78759
(214) 954-5198
ekimber@innodata-isogen.com
www.innodata-isogen.com